Carburetor construction



y 1935.. A. ROUALET 2,008,041

CARBURETOR CONSTRUGTI ON Filed May 15, 1929 V IN VEN TOR NDfiE H0 UALE 71' BY 2 gm: l r ATTORNEY Patented July 16, 1935 match PATENT OFFICE wa oAaBUREToa CONSTRUCTION Andre Roualet, Detroit, Mich, assig'nor to Chrysler; Corporation,Detroit, Mich. a. corporation oi Delaware Ah lic-ationlvlay 13, 1929;.siial. No.362,614

V .22 Claims. (01. 2s1-5o) This invention relates to carburetor construction.

The main objects of my inventionare to provide an improved carburetor having a vaporizing chamber therein in which a supply of gasoline is admitted to the vaporizing chamber when the choke valve of the carburetor is closed, and to provide an improved construction of butterfly choke valvewherein an auxiliary air inlet is opened against yielding pressure by suction from the engine. r a

An illustrative embodimentof this invention is shown in the accompanying drawing, in which:

Fig. 1 is a'view inside elevation of the improved carburetor, a portion thereof being shown in vertical section, taken on the linel.-l of Fig. 2.

Fig. 2 is a sectional view taken on line 22 of Fig. 1. Fig. 3 is a fragmentary, vertical medial sectional View of the improved butterfly choke valve mounted in a carburetor air. inlet. 7

Fig. 4 is afragmentary View, partly in elevation and partly in vertical section, of a. modified construction showing my I improved means for admitting gasoline to the tumor chamber.

Heretofore in the construction of carburetors equipped with auxiliary vaporizing chambers there has been some difiiculty encountered in the matter of having a supply of gasoline present in the fuiner chamber when the choke is closed and the electrical connections made. In the past the supply of gasoline to the fumer chamber was dependent upon' flooding of the carburetor and sometimes such flooding was insufficient to provide the proper amount of gasoline to the fumer. In thepresent construction means are provided whereby a supply of gasoline is always admitted to the fumer chamber when the carburetor is choked'as long as there is a supply in the carbureto-r float chamber. .In the construction shown in the drawing, the carburetor comprises the'customary float chamber "iwhich has communication to themain needle valve control B. Anair inlet 1 commuan electrical heating element I0, to which anelectrical connection is made through a bind.- ing. post ll located at the'lower'encl thereof. xaThe'. float chamber 5is. provided with. a discharge passageway l2? adjacent the lower end thereof, which is controlled by an auxiliary needle valve l3 normally held closed on its seat by a helical compression spring. it which surrounds the upper endof the needle valve i3 and bears between a cover plate It and a washer l6 secured 5 by a pin ll mounted transversely and medially of the valve i3.

Means are provided for raising the needle valve is fromits seat when the choke to the carburetor'is closed and comprises a leverlli pivotally 10 mounted on the stud l9, one end of which engages the under side of a cap 29 mounted on the upper protruding end of needle valve l 3, and the other end of which is engaged by a cam 2| mounted on the outer protruding end of a shaft 22 which-carries a butterfly choke valve 23. Gasoline passing from the float chamber through the discharge passageway 12 and by the valve l3 mixes with air in the space around the needle valve i3 and then passes through a passageway 24 to a vertically disposed passageway 25, the

upper end of which communicates with the'mix-, ing chamber of the'carburetor.

Means are provided for admitting gasoline from the passageways 24 and25 into the vaporizing chamber 9 and comprises a passageway 26 drilled in alignment with the'passageway 24. The inner end of the passageway 26 adjacent the vaporizing chamber 9 is preferably restricted by a threaded plug 21, which has a small aperture An auxiliary valve 29 is journaled on the shaft 22 and is adapted to close'the air passageway 23 when rotated to a closed position. ;A spring 393 is attached at one end by screws st to the valve 23, the other end of said spring bearing against the auxiliary valve 29 fo'rnormally yieldingly urging said auxiliary valve to a closed position. In the modification shown in Fig. 4 of the drawing, the vaporizing chamber 9 is shown'located at a lower level than in the construction shown inFigs. l and 2 and in this modified construc-. tion' the lower end of the vertically disposed pas sageway 25 is counterbored and provided with a plug 32, through which isdrilled a restricted orifice, preferably by a No. 70 drill. A chamber Ea ls provided below the plug 32, which in turn'communicates with the vaporizing chamber 9' bya passageway 34!. The lower end of the counterbore is closed by-a threaded plug 35 screwed there into. i -In the' operation of this improvedcarburetor' the auxiliary or choke needle valve I3 is normally closed on its valve seat by the compression spring l4 so that gasoline from the float chamber 5 will not be admitted to the passageways 24 and 25. Upon closing of the butterfly choke Valve 23, the cam 2i rocks the lever E8 on its pivot l9 so as to engage the underside of the head 20 secured to the top end of the needle valve 53 and thereby raise said valve from its seat. Opening of the valve 13 from its seat permits gasoline from the float chamber to flow through the discharge passageway l2 and past the valve :3 where it is mixed with air and drawn into the passageways 24 and 25 by suction from the engine.

At the same time a small amount of gasoline will enter the passageway 26 and through the restricted opening in the threaded plug 2'! into the auxiliary vaporizing chamber 9, thereby supplying the fumer with the correct amount of gasoline for proper operation thereof.

In order to prevent over-choking of the carburetor when the butterfly valve 123 is fully closed, the tension on the spring 30 is such that the auxiliary valve 29 will open by suction and permit the passage of air into the carburetor, the amount of such air being in direct proportion to the amount of suction to which the valve is subjected.

The opening of the auxiliary valve is proportional to the suction and the degree of opening is predetermined by the tension of the spring 3i) so as to provide for the admission of the correct amount of air required to mix with the fuel in-- troduced into the system while the choke valve is closed. In this manner, the air and fuel components of the mixture are controlled so as to produce a fuel mixture having suitable explosive properties for starting and warming up an internal combustion engine. The freedom of the auxiliary valve to open when the choke is fully closed, as well as when it is partially opened, renders it effective in controlling the air factor of the fuel mixture during initial starting, follow through, and warming up stages of the engine.

Although but one specific embodiment and one modification of this invention have been herein shown and described, it will be understood that numerous details of constructions shown may be altered or omitted without departing from the spirit of my invention as defined by the following claims.

What I claim is:

1. The combination, in a carburetor of the class described having a mixing chamber and an independent auxiliary vaporizing chamber, a float chamber and a choke valve, of means operative by the closing of said choke valve for permitting fluid from said float chamber to pass to said vaporizing chamber only when said choke valve is closed.

2. In a carburetor, a float chamber having an outlet passageway adjacent the lower end thereof, a vaporizing chamber having a fumer therein, a passageway providing communication between said fumer chamber and said outlet passageway, a valve in said outlet between said passageway and said float chamber, choke connections on said carburetor, and means operated by said choke connection for opening said valve only when said choke is closed.

3. In a carburetor having a choke valve, a vaporizing chamber having a ifumer therein, a source of fuel, a passageway providing communication between said vaporizing chamber and the source of fuel, a fumer valve for controlling said passageway, and connections between said fumer valve and said choke valve for opening said fumer valve only when said choke valve is closed.

4. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal running operations including a fuel reservoir, a choke valve in the air inlet of said mixing chamber, an auxiliary starting fuel system communicating with said fuel reservoir and mixing chamber and including a vaporizing chamber, a fuel valve for controlling the flow of fuel from said reservoir into said starting fuel system, and means for operating said choke valve and ,said fuel valve in timed relation so as to open the latter only when said choke valve is closed.

'5. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal running operation, a choke valve in the air inlet of said mixing chamber, a source of fuel in communication with the normal fuel system, an auxiliary fuel system communicating with said source of fuel and communicating with the mixing chamber independently of said normal fuel system and including a vaporizing chamber, a fuel valve for controlling the flow of fuel to said auxiliary fuel system independently of said normal fuel system, and means for operating said choke valve and said fuel valve in timed relation so as to open the latter only when said choke valve is closed.

6. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal running operation, a choke valve in the air inlet of said mixing chamber, a source of fuel in communication with the normal fuel system, an auxiliary fuel system communicating with said source of fuel and communicating with the mixing chamber independently of said normal fuel system and including a vaporizing chamber, a fuel valve for controlling the flow of fuel to said auxiliary fuel system independently of said normal fuel system, a heating element in said vaporizing chamber, and means operable by closing said choke valve for opening said fuel valve only when said choke valve is closed so as to supply fuel to said heating element upon starting.

7. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal operation, a source of liquid fuel communicating with said mixing chamber, an auxiliary fuel system having a vaporizing chamber communicating with said mixing chamber and with said source of fuel,-a heating element in said vaporizing chamber, said auxiliary fuel system having a passage communicating with said mixing chamber independently of said vaporizing chamber, and a fuel valve in said auxiliary fuel system for rendering the same operative only during starting of an engine.

8. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal operation, a source of liquid fuel communicating with said mixing chamber, an auxiliary fuel system having a vaporizing chamber communicating with said mixing chamber and with said source of fuel, a heating element in said vaporizing chamber, said auxiliary fuel system having a passage communicating with said mixing chamber independently of said vaporizing chamber, a choke valve in the inlet of said mixing chamber, a fuel valve in said auxiliary fuel system for controlling the flow of fuel to said vaporizing chamber and to said passage, and means operable by the closingv of said choke valve for opening :said fuel valve so. as. to supply fuel to said passage. and vaporizing chamber during startingof an engine.

9. In 'a carburetor havinga mixing chamber and a conventional fuel feeding system for supplying fuel thereto during normal carburetoroperation, a choke valve for controlling the flow of air through said mixing chamber having an opening therein, an auxiliary fuel systemfor feeding fuel independently of said normal fuel. system to said mixing chamber during commence.- ment'of the operation of said carburetor and including a fuel valve, valve actuating mechanism operable by said choke valve for opening said fuel valve when said choke valve is closed, and yieldable means operable by the suction in said mixing chamber for regulating the flow of air through the opening in said choke valve during the starting stage of the operation of said carburetor. 1 g r 10. In a carburetor having a mixing chamber and a conventional fuel feeding system for supplying fuel thereto during normal carburetor operation, a choke valve for controlling the flow of air through said mixing chamber having an open:-

ing therein, an auxiliary fuel'system for feeding fuel independently of said normal fuel system to said mixing chamber duringcommencementbf the operation of said carburetor and including a fuel valve, a vaporizing chamber in said auxiliary fuel system having a fumer therein, valve actuating mechanism operable by said choke valve for opening said fuel valve when said choke valve auxiliary fuel system having a vaporizing cham- I ber communicating with said mixing chamber and with said source of fuel and including a passageway communicating with said mixing chamber and having an air bleed, means for metering the flow of fuel to said vaporizing chamber, a valve in said auxiliary fuel system for controlling the flow of fuel to said passageway and to said vaporizing chamber, a choke valve having an opening therein located in the inlet to said mixing chamber, control means for said fuel valve operable by said choke valve so as to permit fuel to flow to said passageway and vaporizing chamber when said choke valve is closed, and a yieldable member on said choke valve operable by the suction of said carburetor for metering the flow of air through said choke valve when the latter is closed to correspond with the flow of fuel to I said passageway and vaporizing chamber so as to provide a starting mixture having a predetermined fuel ratio.

12. In a carburetor having a mixing chamber, a fuel reservoir and a normal fuel system for feeding fuel thereto during normal running operation, an auxiliary starting fuel system commu- I nicating with said mixing chamber independently during normal running operation, an auxiliary starting fuel system communicating with said mixing chamber independently of said normal system, and means for alternatively conditioning said carburetor for starting and normal opera- I tions respectively including a valve in said auxiliary fuel feeding system for permitting a flow of fuel theretoonly when said carburetor is conditioned for starting. l

14. A carburetor including a mixing chamber having an air inlet, a normal fuel system communicating with said mixing chamber for feed-'- ing fuel thereto during normalrunning operation, an auxiliary starting fuel system communicating with said mixing chamber, a normally closed fuel valve in said auxiliary fuel system for controlling the admission of fuel thereto, means for conditioning the air factor of said carburetor for starting, andapparatus for opening said fuel valve only when said means is operative.

15. A carburetor including a mixing chamber having an air inlet, a choke valve in said air inlet for conditioning said carburetor for starting, a normal .fuel system communicating with said mixing chamber for feeding fuel thereto during normal running operation, an auxiliary starting fuel system. communicating with said mixing chamber, a fuel valve in said auxiliary fuel system, apparatus for opening said fuel valve only when said carburetor is conditioned for starting by said choke valve, and yieldable means operable by the suction in said mixing chamber for controlling the. supply of air thereto during starting.

16. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal running operations including a fuel reservoir, a choke valve in the air inlet of said mixing chamber, an auxiliary starting fuel system communicating with said fuel reservoir and mixing chamber, a fuel Valve for controlling the admission of fuel from said reservoir into said starting fuel system, and means for operating said choke valve and said fuel valve in timed relation so as to open the latter only when said choke valve is closed.

17. A carburetor for an internal combustion engine including a passage for supplying fuel mixture to the latter and having an air inlet, a choke valve in said air inlet for conditioning said carburetor for starting and having an opening therein, a normal fuel system communicating with said passage for feed fuel thereto during normal running operation, an auxiliary starting fuel system communicating with said passage, a fuel valve in said auxiliary fuel system, apparatus for opening said fuel valve only when said carburetor is conditioned for starting, and yieldable means operable bythe suction in said passage for regulating the flow of air through the opening in said choke during the starting stage of the operation of said carburetor.

18. A carburetor for an internal combustion engine including a passage for supplying fuel mixture to the latter and having an air inlet, a choke valve in said air inlet for conditioning said carburetor for starting and having an opening there in, a normal fuel system communicating with said passage for feed fuel thereto during normal running operation, an auxiliary starting fuel system communicating with said passage, having an air bleed for mixing air with the fuel therein prior to its admission to said passage, .a fuel valve in said auxiliary fuel system, apparatus for opening said fuel valve only when said carburetor is conditioned for starting, and yieldable means operable by the suction in said passage for regulating the flow of air through the opening in said choke during the starting stage of the operation of said carburetor.

19. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal operation, a fuel reservoir communicating with said mixing chamber, a vaporizing chamber communicating with said mixing chamber, a heating element in said vaporizing chamber, an auxiliary fuel system having a passage communi eating with said reservoir and with said vaporizing chamber for delivering fuel to said heater and having a passage for supplying to said mixing chamber fuel in addition to that delivered to said heater, and a fuel valve in said auxiliary system for controlling the flow of fuel to both of said passages and rendering the auxiliary system 01)- erative only during starting of an engine.

20. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal operation, a fuel reservoir communicating with said mixing chamber, a vaporizing chamber communicating with said mixing chamber, a heating element in said vaporizing chamber, an auxiliary fuel system including a passage having an air inlet and communicating with said reservoir and with said vaporizing chamber for de livering fuel to said heater and having a passage for supplying amixture of fuel and air to said mixing chamber, and a fuel Valve in said mixing chamber for controlling the flow of fuel to both of said passages.

21. In a carburetor having a mixing chamber and a fuel system for feeding fuel thereto during normal operation, a fuel reservoir communicating with said mixing chamber, a vaporizing chamber communicating with said mixing chamber, a heating element in said vaporizing chamber, an auxiliary fuel system including a passage having an air inlet and coinmunicating with said reservoir and with said vaporizing chamber for delivering fuel to said heater and having a passage for supplying a mixture of fuel and air to said mixing chamber, and means for opening said fuel valve only during starting of an internal combustion engine.

22. In a carburetor having an air inlet, a choke valve for controlling said air inlet, a vaporizing chamber having a fumer therein, a source of fuel, a passageway'providing communication between the source of fuel and said chamber for supplying fuel to said fumer, a fuel valve for controlling said passageway, and means for opening and closing the latter valve when the choke valve is closed and opened respectively.

ANDRE ROUALET. 

